Latch needle



March 5, 1940. M N 2,192,533

LATCH NEEDLE Filed Aug. 12, 1938 Patented Mar. 5, 1940 UNITED STATES; PATENT OFFICE Max Nebel, Qhemnitz Germany Application August 12, 1938, Serial No. 224,545

-2Claim5.

This invention relates to latch needles for knitting machines and is particularly concerned with a special construction of the needle head to insure good plating in two-thread knitting, in-

eluding the knitting of plush loops from one of the threads. In circular knitting machines for instance plush loop fabric is worked in such manner that the plush thread is sunk above a sinker edge which is located on a higher level than the sink ing edgefor the groundthread, so that sinkin of the plush thread during the descent of the knitting needle is initiated before the sinking of the ground thread. The known almost semicircular head of the needle involves therefore the risk that the ground thread, which is not tensioned at the beginning of the sinking operation and swings to and fro owing to the motion of the machine, is placed once before and once 80 in the rear. of the already tensioned plush thread under the needle head, as the plush thread will always lie in the vertex of the needle head, which is located in the center or almost in the center of the head, so that suillelent space reas mains in front and in the rear of the plush thread for laying the ground thread, although positioning of the ground thread in front of the plush thread is undesirable for the reason that it will cause wrong plating. to The invention proposes to eliminate this defect found also in ordinary plating without the formation of plush loops by constructing the needle head so that the upper portion thereof always extends into an angle which is so much smaller 3| than a right angle that its vertex forms the highest point of the inner space of the head and the one located farthest from the bulging part or breast of the needle shank and that the hooked end of the head on the side of the needle 40 breast extends inwardly toward the needle breast at an acute angle to the axis of the needle in oblique direction.

Asthe sinking vertex of the angle formed in the needle head is the point located farthest in 4.5 front of the axis of the needle and also the highest point of the space which, when the latch is closed, is limited by the latch and the needle head and in which the ground thread moves before the beginning of its sinking operation, the ground so thread following during-sinking is therefore prevented from swinging anywhere in front of the plush thread positioned in the vertex of the needle head when the latch is,closed and is forced to lie always in the ,rear of the plush thread al- 5; ready tensioned by the sinking operation.

- Fig. 2.

By way of example, one form of the needle according to the invention is illustrated in the accompanying drawing, in which Figure 1 is a side view of a knitting needle and shows various positions of the thread within the head thereof and I Fig. 2 is a detail view of the upper portion of the latch.

Referring to the drawing, I is a knitting needle and ID a plush sinker, the needle I during its descent being in a position relative to the sinker 1 It! at which the plush thread 8 is sunk already on the edge II of the sinker-l0 while the ground thread 9 is not engaged as yet by the needle head. The hook I of the head of the needlel has not the usual semicircular shape which leaves some 15 play to the incoming thread, but forms an angle a which is smaller than a right angle, so that in the vertex of the angle, which is the highest point and the one located farthest in front of the axis of the needle in the inner space of the head, the ac plush thread 8 arriving first cannot move inwardly in the direction of the needle breast or outwardly in the direction of the latch I". The point I of the hook of the head I extends in an acute angle'relative to the axis of the needie. When at the beginning of the sinking operation the ground thread 9 is in the position 9, it can be placed in the needle head during the vertical descent of the frame needles, as indicated by the dash and dot line H, only behind the plush thread 8, i. e., in the direction of the needle breast I, even if owing to vibration it slides along the inner edge of the latch l and then along the first part of the inner edge I of the end I of the needle hook. If the ground thread 9 is in the 5 position 9 and slides from the needle head on the inner edge l of-the other side, it will nevertheless be positioned in the rear of the plush thread 8, as indicated, owing to the relative motion to the needle in the direction 11-4! imparted m to it by the vertical downward motion of the needle I.

Such unintentional variation of the position of" the thread may be due not only to "oscillation of the thread but also to irregularities produced by the needles if they are not exactly arranged in a circular line but somewhat outside or inside the needle circle owing to the play in their bearing required for their movement. In order to cause the latch I properly to enclose the end of the 0 needle hook the eyeor groove I" in the spoonshaped portion 1 is open on top, as shown in This accidental displacement of the ground thread relative to the plushthreQ due'to irregularities in construction as well as to oscillation oi. the thread produced by the machine is eliminated in a simple'manner by forming the needle head in the manner described. I' claim:

' 1. A latch needle for knitting machines, comprising a head forming a hook at its upper end which completes the open side of the headon the side of the needle breast and a latch swim:- ably arranged at the base of the head on the open side thereof which can thus be opened or closed as required and' having a spoon-shaped portion at its free end abutting against the hooked end or the needle when the open side of the head is closed, the upper portion of said head extending inwardly into an acute angle which is so much smaller than a right angle that its vertex constitutes the highest point and the one located farthest in front of the needle breast in the inner space of the head, the hooked'end of said head positioned-on the side of the needle breast extending inwardly in oblique direction at an acute angle to the axis of the needle and thus in the direction of the needle breast.

2. A latch needle according to claim 1, wherein the spoon-shaped portion of the latch has an 

